Field of the Invention
The present invention relates to a trim mounted to a door opening of a car, or the like, and, particularly to an improvement in a metallic trim insert embedded in the trim as a core member.
The trim is used, for example, as a shock absorber, a decorative member or a sealing member such as a weather strip attached to a door opening of a car body. A trim of this kind often has an insert of sheet metal embedded in a long molded section, of a material such as rubber or synthetic resin, to allow the trim to retain its shape.
The sheet metal insert embedded in the trim, for example the element denoted as 100 in FIG. 27, is formed of a plurality of core pieces 101 arranged parallel to each other at regular intervals and a bonding portion 102 for connecting the core pieces 101 to each other in the longitudinal direction. Alternatively, in another insert 100A (100) shown in FIG. 28, there are two bonding portions 102 and 103 for connecting the core pieces 101 to each other. As shown in FIG. 29, each of these inserts 100 and 100A is formed by a stamping process to be a flat sheet which is then fed to an extrusion molding process of a body of the trim while maintaining the flat shape and is embedded therein by a monolithic molding, after which it is bent in the widthwise direction of the trim to have a predetermined cross-sectional shape as shown, for example, in FIG. 26 and described later. At this time, the bonding portion 102 or 103 is severed and broken, if necessary, by a separator or the like.
As stated above, the insert for the trim is subjected to a monolithic molding process, together with a long molded trim section, and bent thereafter. The insert must maintain an engagement force at a position to which the trim is mounted. Accordingly, the insert for the trim must, of course, have a shape-retention ability as a core member of the bent core for the trim, as well as a rigidity, enough to resist a shearing force of the extruded material during the extrusion molding process. Generally, since the core piece 101 in the insert 100(100A) of this kind is of an elongate shape, for example, having a width in a range from 2 to 3 mm and a length (a size of the insert in the widthwise direction as a whole) in a range from 20 to 40 mm, it is necessary that the insert has a thickness to some extent; for example, sheet metal having a thickness of 0.4 to 0.5 mm is used at present.
In this connection, if the thickness of the sheet metal used for the insert is further reduced for the purpose of decreasing a weight or cost of the molded trim, or effectively using material resources, there is a risk not only that the shape-retention ability as the core member becomes insufficient, but also that the rigidity is lowered, whereby the core pieces are deformed by the pressure of a resin during the monolithic molding of the trim to disturb the parallel arrangement of the core pieces and deteriorate the function of the insert. Therefore, there was a problem in that the thickness of the metal sheet could not be further reduced. However, the reduction of thickness of the insert results in many merits; such as the lowering of the material cost, the reduction of a weight of parts, as well as the effective use of material resources.
The present invention proposes a novel insert for a trim improved mainly in functions such as rigidity or strength in view of the above-mentioned problems. Thereby, a novel insert for a trim, and a novel trim using the same, capable of reducing a thickness thereof without any deterioration of the function of the insert, lowering the material cost, decreasing a weight of parts as well as effectively using material resources, are provided. Also, the present invention proposes a structure of an insert for a trim capable of adjusting the rigidity or the strength of core pieces if necessary.